Bender AGH420, Руководство пользователя

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Function
20 isoEV425_D00126_09_M_XXEN/03.2019
sages "-R1" and "-R2" indicate an insulation fault assigned to conductor L2/-. If
an assignment is not possible, for example in the event of a symmetrical insu-
lation fault, the messages corresponding to "+" and "-" are shown together.
The message "test" indicates a self test.
The message "S.AL" indicates a so-called "device start with alarm". After con-
necting to the supply voltage and setting the parameter value to "S.AL = on",
the ISOMETER® starts with the insulation measurement value
R
F
= 0 Ω and
sets all activated alarms.
The alarms will be cleared only when the measured values are up-to-date and
no thresholds are exceeded. In the factory setting "S.AL = off", the ISOMETER®
starts without an alarm. It is recommended that the value set for the "S.AL" pa-
rameter value is identical for both relays.
3.2.6 Measuring and response times
The measuring time is the period essential for the detection of the measured
value. The measuring time is reflected in the operating time
t
ae
.
The measuring time for the insulation resistance value is mainly determined
by the required measuring pulse duration, which depends on the insulation
resistance
R
F
and system leakage capacitance C
e
of the system to be moni-
tored. The measuring pulse is produced by the measuring pulse generator in-
tegrated in the ISOMETER®. The measuring times for
C
e
, U
L1e
, U
L2e
and R % are
synchronous. System disturbances may lead to extended measuring times. In
contrast, the time for the nominal system voltage measurement
U
n
is inde-
pendent and considerably shorter.
Total response time
t
an
The total response time t
an
is the sum of the operating time t
ae
and the re-
sponse delay time t
on
.